Any sort of guide to power supplies for 8800 nvidia cards?

[ODogg]

I'm ordering a new computer soon and i've talked with all kinds of companies, they all seem to give me different information on what sort of power supply is needed with a nvidia 8800 GT video card. One company said I should def. have 1000watt power supply and another said 500 watts was fine.

The system i'm getting is as follows:

THERMALTAKE, Tsunami Black Mid-Tower Case w/ Window, ATX, 400W PSU, Aluminum ANTEC, NeoPower 650 Blue High Efficiency Power Supply, 650W, 24-pin ATX12V EPS12V, SLI Ready, 120mm LED Fan, 5-Year Warranty
ASUS, P5N-E SLI, LGA775, nForce 650i SLI, 1066MHz FSB, DDR2-800 8GB /4, PCIe x16 SLI /2, SATA RAID 5 /5, HDA, GbLAN, FW /2, ATX, Retail
INTEL, Core™ 2 Quad Q6600 Quad-Core, 2.4GHz, 1066MHz FSB, 8MB (2 x 4MB) L2 Cache, 65nm, 105W, EM64T EIST VT XD, Retail
OCZ, 2GB (2 x 1GB) Gold GX XTC PC2-6400 DDR2 800MHz CL 5-5-5-12 SDRAM DIMM, Non-ECC
ASUS, EN8800GT/HTDP/1G/A, GeForce® 8800GT 600MHz, 1GB GDDR3 1800MHz, PCIe x16 SLI, DVI /2, HDTV-Out, Retail
WESTERN DIGITAL, 150GB WD Raptor®, SATA 150MB/s, 10000 RPM, 16MB cache
LITE-ON, LH-20A1L Black/Beige 20x DVD±RW Dual-Layer Burner w/ LightScribe, SATA, Retail

I know that the power supply I am getting is ok for my one video card I have now, the 8800GT, but what if i want to add a second? I would like to do that sometime in a couple of years.

Honestly I've heard all sorts of things so i'm wondering if anyone knows in general a guideline to what an 8800 needs and/or your opinion on whether i'll have to upgrade my power supply, if so to what?

Sure i'd like to just get a 1000watter to be honest and not worry about it but the prices go up in a hurry and i'm trying to keep this computer in budget (unlike my last one).

[mudtiger]

Re: Any sort of guide to power supplies for 8800 nvidia cards?

You do not need 1000 watts unless you plan on a lot of hard drives, overclocking, a lot of fans, 2 or more vid cards, and a lot of pci cards.

I have a near identical system, q6600, 8800gt, etc, and a 550 watt corsair psu is fine. You could get away with 450...maybe.

If you are serious about wanting to go SLI, then you make sure you get 36 amps total on the 12v rails. As far as watts for SLI, I'd shoot for 600+. 750 should be more than adequate. There is absolutely no need to go to 1000 watts.

[ODogg]

Re: Any sort of guide to power supplies for 8800 nvidia cards?

Hey thanks man, also i found this utility which is pretty cool, it said i'd need a 524 watt power supply with 1 card and if i added another i'd need 589 watts so I think the 650 watt power supply will work well for me.

http://www.extreme.outervision.com/PSUEngine

Check that out, it's pretty neat.

[mudtiger]

Re: Any sort of guide to power supplies for 8800 nvidia cards?

Just remember going by watts isn't the end all and be all for psu's. You need to look at the amps on the 12V rail. Usually psu's now have multiple 12v rails, so add 'em all up(not exact, but close enough to total 12v). You need at least 22 (although you might get away with 20) for a single 8800gt and you want double that to do SLI.

edit...edit - all screwed up today, SLI in theory needs double the single card, but you can get away with less.

Here's some good reading if you are bored

http://www.jonnyguru.com/forums//showthread.php?t=1036